Off-topic post because I couldn't find a forum for your Gatorade Cooler, but just a couple things that caught my eye:

Euclid -> Safe. As long as it sits in it's box, and no LOL Foundation D-Class opens it up, it should be fine. Unless it starts drawing people towards it with "super-spooky mind powers," then they need armed guards and monthly psychological evaluations on personnel, I would call it safe. (Not a fan personally of things that just draw you to them, because I think of that as being "anomalous for the sake of being an anomaly," but some like it.)

Indestructibility. Again, since it's not alien or from the future, I'd NORMALLY say that was thrown in for the heck of it… But that one has a Wondertainment-esque feel to it, so I have neither good nor bad to say on it, just something to consider.

The Interview (This one and the Seth Rogan movie). This really broke the tone of how serious the overall document was. The nonchalance the head of Gatorade's marketing towards the fact that someone found their top-secret, dangerous prototype, and her reference to some shadow organizations missed it's goal by a wide margin, and I'd suggest a brush-up on it.

— Gatorade would not be comfortable with admitting something like this to a person with a recording device. They would be in deep horse feces if the media ever got wind of this prototype.

— The woman "just pulling your leg"about mysterious organizations is either really unprofessional sounding, or she's obviously saying ironically that they have worked with mysterious organizations, in which case the Foundation would stop mucking about with contacting Gatorade by phone, like a Fox News opinion columnist trying to expose the evil school system, and start raiding Gatorade for every shred of info they have on how they built indestructible, practically magic Gatorade jugs, beginning with that warehouse she may as well have given coordinates to.

—The Foundation isn't going to let itself be stopped by bureaucracy, and would pursue them a bit more viciously than one interview and unreturned calls. Not when these people are practically waving around neon signs saying "WONDERTAINMENT AND PROMETHEUS LLC HERE."

All said, I like that one a lot. The strange, addictive fantastic object that wasn't a Wondertainment object, but could have been, all good stuff. But would suggest a once-over of the interview, but NOT deleting it. The Foundation would definitely get an interview - whether Gatorade wanted to or not. Just ending it at "Gatorade declined to comment," or something like that makes an organization that deals with guys like -076 or -682 look like fools.

I feel like this thing is Safe. It doesn't eat or drink, and you can probably keep it in a box or an airtight terrarium.

Special Containment Procedures: SCP-xxxx is to be held in a standard containment cell

Why does it get an entire cell to itself? It's a towel.

with a door that provides absolutely no space below, above or on the sides of the door

Redundant use of "door". Also, "airtight door" will suffice. Besides, you'd think Foundation cells already don't have spaces between the door and the frame that would allow for escape. They've been containing things for years.

to prevent escape,

You don't need to justify. It's assumed that containment protocol is in place for logical reasons.

and given a liter of [REDACTED]

Don't redact anything in containment, otherwise no one knows what to do. These are basic instructions anyone interacting with the thing should know about. There's no reason to withhold info, especially in emergencies.

twice a day.

Who's doing the giving? Is it automatic via chute? Seems to be safer if it's automatic.

Staff are allowed to visit SCP-xxxx, due to it's friendly manner.

Should be "its" not "it's", since you only use "it's" when you mean "it is". Also, the Foundation doesn't allow "visits". People need proper clearance for accessing SCP objects.

No visits to SCP-xxxx's cell are allowed after Incident xxxx-█.

Why were visits allowed in the first place? Unless contact is required, it seems much safer to just keep the thing locked up all the time. Preferably in a small box, where it can't run loose and attack people.

Use blackboxes for the name. Dr. redacted looks silly and unprofessional.

went into SCP-xxxx's containment cell to feed it, (Staff had forgotten to feed it earlier that day),

Yeah, this wouldn't happen. The Foundation is a professional organization, and they should have an automatic feeding system for something so dangerous.

when SCP-xxxx latched onto his arm and

Why wasn't the doctor wearing protective gear of some kind?

started to suck out Dr. [REDACTED]'s bodily fluids.

So… blood, bile, sweat, urine… how would anyone be able to figure out that this was happening?

By the time other staff had gotten in,

Who are these "other staff", and "gotten in" to what?

Dr. [REDACTED] had already turned pale due to fluid loss.

Why didn't he try to remove the towel himself? Why wasn't he informed of what the towel was capable of? …Why was this guy feeding the thing anyway?

The staff on duty was able to remove SCP-xxxx,

If they arrived late enough for the guy to turn pale, they don't seem like they're on-duty.

and saved Dr. [REDACTED].

How? Did they rush him to the medical ward? Was he automatically okay once the towel was removed? The effects and progression of events are really unclear here.

Addendum-01: After his injuries recovered,

The doctor does the recovering. The injuries are what he's recovering from.

Dr. [REDACTED] told foundation

Foundation

personnel about the incident.

…but he is a member of Foundation personnel. Also, why didn't anyone hear about this immediately after it happened?

He said that the bristles on SCP-xxxx, "Stuck out like shark teeth."

This is too casual for scientific writing.

Due to Dr. [REDACTED]'s testimony, and security footage,

…they had this thing on camera and never ran tests with it to determine its threat potential?

foundation staff

Foundation

were able to determine that SCP-xxxx had mimicked a Vampire Squid.

…how? Vampire squid don't have shark teeth.

After incident xxxx-█,

Incident

SCP-xxxx has been more hostile towards staff,

How can anyone tell if a towel is hostile or just hungry?

and has not cooperated in any attempted interviews.

Why on earth would they interview something that can't communicate?

Overall, there are many, many issues with this. A lot of the scientific approach is faulty, and the Foundation personnel seem unrealistically incompetent.

I recommend taking a break from writing drafts for the moment, and focus on reading some quality SCP articles to get a feel for what the site is expecting these days.

If you're looking for SCPs that are a good example of current site standards, I recommend reading the high-rated Series II and III articles (SCPs with numbers from 1000 to 2999). There are many inspirational articles in Series I, but articles written four or more years ago are less likely to be up to current community expectations, even if they've got a lot of upvotes. Remember to pay attention to how old an article is when deciding if you'll use it as a guide or not; you can (and should!) check article age by clicking the "History" link at the bottom of a page, and looking for the page creation date.

Furthermore, you should get your ideas critiqued in the Ideas and Brainstorming forumbefore you start drafting, so you don't waste your time writing up a draft for an idea that isn't good to begin with.

Reasonable containment procedures. Would cut down on the wording by replacing the "no room to escape from above, below, etc." with "airtight/heremetically sealed/reinforced door." It's a towel, and unless it can liquify itself or has a knack for sliding through small cracks, a locked, guarded and monitored room will suffice. Also, if no staff are allowed contact, maybe you should say how food is delivered without contact.

The fact that staff were at one point allowed to enter the containment unit seems a bit odd in that it doesn't seem they would want to. It doesn't strike me as something like tickle monster, or -343, but if the staff entered because they liked being with it for some reason or other, be sure specify it.

Description:
It's sounds pretty original, but perhaps you should expand on what happens when it turns into a human. The sudden attack was unknown to the Foundation initally, but it was also unknown to the reader as well.

Would consider changing Dr. [REDACTED] to black boxes instead of [REDACTED]. Would also consider putting that [REDACTED] over the fact it was his body fluid being sucked out, and [REDACTED] the fact that he was turning pale or exactly what the doctor said after he recovered, but leave the fact that he recovered open to see, and not both.

In terms of how good this is right here, I'd say it's already in the top 20% (with 0% being -173), and I'm not saying these suggestions are my ten commandments to you, just a second opinion. The only real qualm I have is the Containment Procedure and the mentioned ability to mimic humans, and then not expand on it, among other little quirks.

EDIT: Read through one more time. Change the measurement of the towel to meters. That's something that I would strongly recommend.

EDIT 2: Noticed Zyn, who is wiser than me posted here. Think about his suggestions as priority over mine. Anything that multiple people notice in an article should be looked at too.